Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
1–10 of 51 posts
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#2the article doesn't go on to explain more on how this could have happened, I would assume they run some tests on the specs, or some kind of simulations (I am obviously not an expert in making submarines) but considering they are so expensive, wow, amazing. Someone put a decimal in the wrong place and nobody noticed , what are the odds of that happening!
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#3> “Apparently somebody in the calculations made a mistake in the very beginning and nobody paid attention to review the calculations,” he said.
Supporting the old software engineering folklore that the earlier a bug is introduced (and the later it is found) the harder and more expensive it is to fix.
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#4> And a former Spanish official says the problem can be traced to a miscalculation — someone apparently put a decimal point in the wrong place
Sloppy reporting. Spain uses a decimal comma.
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#5Other explanation, more in line with the reality of Spanish reality.
http://www.thelocal.es/20130520/530-million-bill-for-spains-...
> The president of the Navantia board has defended the work of the company's Cartagena shipyard and complained of "meddling" by unqualified people.
> He explained that it had been reported as far back as 2005 that the development process was not being properly followed and that there was a lot of necessary improvisation due to the addition of new elements at the request of the Ministry of Defence.
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#6> And a former Spanish official says the problem can be traced to a miscalculation — someone apparently put a decimal point in the wrong place Sloppy reporting. Spain uses a decimal comma.
This is an engineering calculation, it may not be guaranteed based on who they're working with and which standard they use.
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#7the article doesn't go on to explain more on how this could have happened, I would assume they run some tests on the specs, or some kind of simulations (I am obviously not an expert in making submarines) but considering they are so expensive, wow, amazing. Someone put a decimal in the wrong place and nobody noticed , what are the odds of that happening!
It's not as unlikely as you'd think.
Even in the U.S. we used to routinely have to put in slop factors to account for contractors that would routinely deliver gear in excess of spec. It wasn't until the most recent SSN class that they were able to finally hold the line against the contractors and sub-contractors... but at least the design itself would have weighed what was expected.
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#8The other key figure is that the entire submarine weighs 2,200 tons.
The sub was 3% too heavy and it will cost $14 million to fix, big woop, worse happens 1,000 times per day all around the world.
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#9From the headline I thought that somehow they had attached 70 tons more weight onto the thing than they wanted (e.g. accidentally made the hull too thick or something).
But from reading the article, it seems it's actually they just miscalculated the final weight based on the specs. Their miscalculation had it coming in 70 tons under its actual weight (which is 2200 tons). So the sub was built to spec, it's just the buoyancy calculations were wrong.
Re: Spain builds submarine 70 tons too heavy by putting a decimal in the wrong place
#10The other key figure is that the entire submarine weighs 2,200 tons. The sub was 3% too heavy and it will cost $14 million to fix, big woop, worse happens 1,000 times per day all around the world.
Just to add to that - it's $14 million on top of a $2.7 billion project.